Mount Vesuvius wreaked havoc on Pompeii, the volcano devastated the area of present-day Naples. In a paper being published online this week by the Proceedings of the National Academy of Sciences, researchers report that the eruption occurred nearly 4,000 years ago and spread as many as 15 miles from the volcano, burying people under thick deposits of ash and pumice (see image). The scientists note that that a comparable blast in the future could destroy Naples and neighboring areas.